Azo dyestuff and process of preparing the same



PetentedJune 13, 1933 i UNITED STATES,

PATENTOFFICE eunnnmnnn, or scorn :Aim narrate, n. mimrnY, or iurnwnuxnn;

WIISCONSIRASSIGNORS,BY MESNE ASSIGNMENTS, 'ro ELI. nuronr DE NEMOURS a; t a

i No Drawing.

is characterized eral formula:

ft a a a. i in whicl1R R ,land R stand for aromatic residues or groups and 1n WhlCh R may or comm, AcoRronArIoN or DEL WA E norm-emu masseuse or rnnrnnme 'rrrn SAME p p This invention relates to a process presparing anoveltype of azo ddyestufls which I by containing the 1 terephthaloyl residue. at a 1 More particularly, it is an object ofthls inventionlto deyiseiwa process for preparing polyazo dyes of thefollowi ng probable gendroxide, {sodium carbonate, =sodiuml acetate,

Application filed December 322, 1930. sensitive. 504,211!

(in which R wmay be ga n aryl residue or. two or more aryl .bodiesulinkedyyito gether by i bl sN-- groups) with one mole derivative thereof, in the?presenceof a suit able condensing agent such as sodium .1 hyor otherflsubstance capabletof neutralizing may not contain further azo groups. Dyestufis of-the above type are characterizedby exceptional fastness to light and to washing. Our process is; therefore exceptionallyv'aluable because it leads to a series; :oi? commercially valuable dyestuffs useful fori dyeing cotton, wool, silk, rayon,etc.

of dyestufis, hitherto not known, and not obtainable by a the hitherto known methods. 1 As a special branch of our novel series of dyestuffs may be mentioned the group in which R R and R stand for aromatic residuesoftheben-zene or naphthalene sefries, which maybe further substituted by alkyl, alkoxy, halogen, sulfonicacidqor'siinilar groupsnbut which do not contain any freehydroxyl or amino groups. Thisparticula'r group of dyestufi's is characterized by g ving orange to brown shadesof good brilliancy and excellentjjfastness to light and to washing.

QOur process is particularlyuseful for the z qrepa'ration of dyestuffs of the above general formula which have no free OH or QNH groups in theR residue since these a v dyestuffs cannotbe prepared by the method" halogen. To impart water-solubility there- 1 to, the entire dyestuff shouldcontain at least 1 twojsulfonicacid groups. In the case where R R and R}; (and B5B, and are so iydroxyl oralnino group, orange to brown g to these.

ionic-acid nionosodium salt, are dissolved in? Our "novel process infgeneralconsists of ou yginstead of With a Sin! gle aniino-polyazo compound of the type use two, difi'erentfiamino-polyazo compounds obtainingthereby a dyestufi' which contains a at leasttln part a anfunsymmetrical compound, of the type: p a

As statedabove R Rguand R (or R R i and R5) are aromatic residues and may be chosen that the final dyestuff contains no free shades may be ()btained.

The-following examples i will ffurther illustrate0ur invention, but it should be understood that our invention is-not limited p The Parts given are partsby weighty. i i, WE'ammpZe 1 p parts of? 2 -naphthylaniine 6,S disuIQ 2,000 pa or wate and d flZotiZdiifi the usual nanner at about 5 p by inea ns of 348 parts of 20 B. hydrochloric acidfand 69 parts of sodium nitrit 35OQp'arts of acetate (cr;ystals) and part 101? sex i methyl-aniline-omega-sulfonic acid (sodium salt) are added, and the mass stirred for about 15 hours. The coupling product is now salted out, filtered, and boiled in 10% caustic soda to hydrolize off the methylsulfonic acid group. After neutralizing the excess caustic soda, the amino-azo compound is salted out, isolated by filtration,

dissolved in 5,000 parts of water, an'd'dia zotized in the usual manner, at about 15 (3., by the addition of about 52 parts of sodium nitrite (or an amount just sufficient. to effect diazotization) and 290 parts of 20 B. hydrochloric acid. After stirring for 3 hours the diazotization. is complete. 96 parts of meta-toluidine, dissolved in 1,000 parts of water and 104 parts of 20 B. hydrochloric acid, are now added, and the coupling is completed by the gradual addition of 210 parts of sodium acetate (crystals). The mass is now stirred for 12 hours, acidified with 232 parts of 20 B. hydrochloric acid, heated to 60C., salted out and isolated by filtration. The amino-disazo dyestulf is now dissolved in 10,000 parts'of water containing 40 parts of caustic soda and heated to C. 106 parts of soda ash and 100 parts ofterephthaloyl chloride, are now added over a period of about hour. The mass is stirred for another 2 hours at about 72 to 78 0., and the dyestuff salted out and filtered. The resultant product is an orange powder, soluble in water to an orange solution and in concentrated sulfuric acid to a violet solution. It dyes cotton light orange shades of excellent fastness to light and to washing. Its structural formula in the free acid state is most probably as follows 0 CH3 SOaH we as Ea-ample? 173 parts of ,sulphanilic acid (aniline-psulfonic acid) are dissolved in 4,000 parts of water and 40 parts of caustic soda and cooled to5 C.; '69 parts sodium nitrate are acid (the 1,6-Cleves' acid may be used instead dissolved in 3,000 parts Water'is adde and the coupling completed by stirring for 12 hours. The monoazo compound thus formed is converted into the sodium salt by the addition of 40'parts of caustic soda. 76 parts of sodium nitrite are now added, the solution agitated, and 580 parts of 20 B. hydrochloric acid are introduced. After stirring for 4 hours the sparingly soluble diazo compound is salted out, filtered off, and pasted in 6,000 parts of ice and water. A solution of 107 parts of metatoluidine dissolved in 1,000 parts of water and 116 parts of 20 hydrochloric acid is now added.

he coupling is completed by the gradual addition, while stirring, of 140 parts of sodium acetate (crystals) dissolved in 1,000parts of water. The disazo dyestuff formed is isolated by the addition of 290 parts of 20 B. hydrochloric acid, salting and filtering. The isolated disazo dyestuif is dissolvcd'in 10,000 parts of hot water (about C.) and 40 parts of caustic soda. 106 parts of soda ash and 100 parts of terephthaloyl chloride are now added. The reaction solution is stirred for 2 hours at 72 to 78 C. and the dyestufi isolated by salting and filtering. The resulting dyestuit is a light. brown powder, soluble inwater to a brown solution, and in concentrated sulfuric acid to a green solution. It dyes cotton in light brown shades of excellent .fastncss to light and to washing. In the form of its free acid it has most probablythe following formula: i

. I I CH3 $0311 S OsH Example 3 SOaNa S OaNa and 569 parts (1 mole) of the disodium salt of theramino-disazo dyestuff prepared accordingto Example 2, and having the following probable formula: H2N -N= N N=NO-SOQNa f tier;

l SOaNa are dissolved together in 20,000 parts of water; 212 parts of soda ash are introduced and 203 parts (1 mole) of terephthaloyl chloride are added. The mixtureis stirredfor two'hours at 72 to 78 (1., and the condensation product isolated by salting out and filtering. The resulting dyestuif dyes cotton in light brown shades. It dissolves in water to give a brown solution, and in.

concentrated sulfuric acid with ablue color.

The dyestuif is probabl a mixture of the two symmetrical dyestu 5 obtained respec tively in Examples 1 and2, and a third, un

symmetrical dyestufi' having in the form of dyestuffs, provided a total of two moles of formula: 15 s itsfree acid most probably the following i "If desired, the relative proportions of these individual polyazo dyestuffs in the mixture may be varied by" starting with unequal quantities of the original disazo these disazo dyestuffs is condensed with 1 mole (more or less) of terephthaloyl chloride. Intermediate shades may thus be obtained ranging'from orange to brown.

Ina similar manner trisazordyestufi's may be used as starting materials to givevarious symmetrlcal or unsymmetrical. condensation products. Similarly, mixtures of trisazo and disazo dyestuffs may be'usedas initial materials. As an example of'autrisazo dye stuffs particularlyuseful for the above purpose, the one having the following formula in the form of its free acid may be mentioned handf ex cesse s of the amino-polyazo bodies in place of the terephthaloyl halides in the above examples.

a In the claims below, it should be understood that where new productdxdyestuifs, or artlcles of manufactures. are claimed, we

mean to include those bodies'notonly in substance, but also in whatever state they exist when applied to materials dyed, printed, or pigmented therewith. a a

We are aware that numerous details of the process may be varied through a wide range without departing from the principles of this invention, and we, therefore, do not purpose limiting the patent granted hereon otherwise than necessitated by the prior art.

We claim as our invention V l. The process of preparing a polyazo dyestuff containing a terephthaloyl group, which comprises condensing amino-polyazo compounds with a terephthaloyl halide which may be halogen substituted in the benzene nucleus.

2. The process of preparing a polyazo dyestufii containing a terephthalcyl group,

which 1 comprises condensing amino-polyazo compounds witha terephthaloyl halide sub stantially in the ratio of'2: 1 moles which may be prepared by diaz otiz ing amino-azo-benzene-disulfonic acid, coupling to meta-toluidine, rediazotizing and coupling phthaloyl body, which excess decomposes again to meta-toluidine.

While we have indicated the use of the two moles of amino-disazo compound tosubstantially one mole of terephthaloyl halide in the examples, it is tobe understood that this proportion neednot be adhered tov precisely. On the contrary, the reaction may he facilitated by the use ofan excess oftereduring the prolonged stirringofthe condenw sation mass into soluble compoundspwhich are; separated from the precipitated dyestuff during the filtration. step. On the other 3. The process of preparing an azo dyestuff of the type:

C O-NHRsN=NRz-N=N-R1 which comprises condensing two moles of an amino azo compound ofthe typez a N R3 N N R N N R i in which R R andR are aromatic residues of the benzene or naphthalene series and in which R may be an azo chain of arylbodies of, thelbenzene or naphthalene series linked together by -N =N- v groups, with. substantially one mole of a terephthaloyl halide, in the presence of a condensing agent.

4. The process of preparing an azo dyestuli of the type:

which comprises condensing an azo-amino compound of the type:

H NR N=N R -N=NR in which R R and R are aromatic residues of the benzene or naphthalene series and in which R may be an azo chain of aryl bodies of the benzene or naphthalene series linked together by -N=N groups, with a terephthaloyl halide, in the presence of a condensing agent.

,5. The process of preparing stuff of the type:

an azo dyewhich comprises condensing with a terephthaloyl halide in the presence of a condensing agent two difi'erent amino-azo compounds of the type:

H N-R -N=l l-R -N=N-R and r H NR l l=l lR N=N-R in which R R R R R and R are aromatic residues of the benzene or naphthalene series and in which R and R may be azo chains or aryl bodies of the benzene or naphthalene series linked together by.

N=N groups.

6. The process of preparlng an azo dyestulf of the type:

in which R R and R are aromatic residues of the benzene or napthalene series and in which R may be an azo chain of aryl bodies of the benzene or naphthalene series linked together by N=N groups, which 'comprises diazotizing a compound of the type: R N=N-R NH coupling to a compouhd of the type: R -NH and condensing the resulting amino-polyazo compoundsubstantially in the ratio two moles to one mole with a terephthaloyl halide, in the presence of a condensing agent. r

7. The process of preparing a tetrakisazo dyestufl of the type:

inwhich R R and R stand for the same or different aromatic residues of the benzene 0r naphthalene series, but in which R contains no free OH or YH groups, which cornprises condensing 2 moles of an amino-disazo compound of the type R N=NR N=N-R with substantially one mole of a terephthaloyl halide in the presence of alkaline condensing agents.

9. The process of preparing tetrakisazo dyestuifsof the general formula:

in which R B and R stand for the same or different aromatic residues of the benzene or naphthalene series, but in which R contains no free OH or NH groups, which comprises diazotizing an amino-azo compound of the type R '-N=N R NH coupling with a compound of the type R -NH and condensing the resulting amino-disazo compound substantially in the ratio 2:1 moles with a terephthaloyl halide in the presence of alkaline condensing agents. P

10. The process of preparing tetrakisazo dystufl's of the general formula:

CO-NHRaN=NRs-N=N-R1 10 in which R R and R stand for the same or dllierent aromatic residues of the benzene or naphthalene series but in which R contains no free OH or Nl-l groups, which comprises dlazotizing anaryl amine of the type R -NH coupling to an ar'ylamlne of the type It -NH rediazotizing and coupling to an aryl amine of the type R -NH and fastness to light which comprises, condensing a secondary disazo dyestuff' of the general type R N=N-R N=NR -NH in which R R and R are the same or different aromatic residues of the benzene or naphthalene series containing no OH or NIL groups, with a terephthaloyl halide in the presence of alkaline condensing agents.

12. The process of preparing orange to brown azo dyestuffs, fast to light and to washing, which comprises diazotizing aniamino compound of thetype:

[R N=NR NH (SO H),, and coupling to a compound of the type R -NH in which formulae R R and R are the same or different aromatic residues of the benzene or naphthalene series containing no OH or NH groups and in which an is an integer not greater than 3, and condensing the resulting amino-disazo compound substantially in the molal ratio 2: 1 with terephthaloyl chloride in the presence of an alkaline carbonate.

13. The process of preparing an orange dyestufl' of good fastness to light and to washing, which comprises diazotizing 2- naphthalamine-6,8-disulfonic acid monosodium salt, coupling to 'aniline-omega-sulfonic acid, hydrolyzing the resulting sulfamino-azo dyestufi to give the free amine,

rediazotizing, coupling to meta-toluidine, and condensing the resulting a1nino-disazo dyestufl substantially in the molal ratio 2: 1 with terephthaloyl chloride in a weakly alkaline medium.

14;. The process of preparing alight brown dyestuif of good fastness to lightand to washing which comprises diazotizing suljianilic acid, coupling to Cleves acid, rediazotizing, coupling to meta-toluidine and condensing the amino-disazo dyestufi thus obtained substantially in the ratio of 2:1

moles with terephthaloyl chloride" in a weakly alkaline medium. a y

15. Asnew products, dyestufls of the following probable general formula:

in which 00 is hydrogen or halogen and R R 11 ,3 R5, and R are aromatic residues of the-benzene or naphthalene series butin which R and R are free from auxochromic groups and R and R may beazo chains of arylubodies of the benzene or naphthalene series linked together by -N=N groups.

16. "As new products, dyestufls of the following probable general formula:

in which R is an azo chain of aryl bodies of the benzene or naphthalene series linked to; gether by N=N, groups and R and R are aromatic residues of the benzene or naphthalene series containing no OH or NH groups. a a l a i a 17. As new products, dyestuffs of the fol: lowing probable general formula:

in which R R R ,R R and R are aroin which R R and R are aromatic residues of the benzene or naphthalene series containing no OH or NIL groups.

a 19. As new products, dyestuffs of the fol lowing probable general formula:

in which R R and R are aromatic residues of the benezene or naphthalene series said dyestuff containing at least two sulfonic groups but no free OH or NH groups and dyeing cotton in orange to brown shades, of good fastness to light and to washing.

20. As a new product, a dyestuif comprising a compound having in the form of its free acid the following probable formula:

SOaH

CH3 p SOaH (saga M -SO3H said dyestuif dyeing cotton in light orange shades of good fastness to light and to wash- 111 51. As a new product, a dyestuff comprising a compound having in theform of its free acid-the following probable formula:

S OaH said dyestuff dyeing'cotton in light brown shades of good fastness to light and to washmg.

In testimony whereof, we have hereunto subscribed our names at Carrollville, Milwaukee County, Wisconsin.

IVAN GUBELMANN. ARTHUR R. MURPHY. 

